Earlier this year the restaurant chain, which first opened a restaurant in 2008, revealed it would close 12 sites and ask for rent cuts at 11 more as part of a CVA (company voluntary arrangement) as it struggled with debts of £71.5m. More than 600 people lost their jobs, but Mr Oliver said that he had no choice but to restructure in order to preserve the 1,600 jobs that remain.

Since 2015, when he hired his brother-in-law Paul Hunt to restructure his companies, there have been many redundancies. In a new interview with the Financial Times, it has emerged that staff who were let go were expected to sign non-disclosure agreements preventing them from discussing Oliver or members of his family in public.

After the impending closures of Jamie Oliver’s restaurants became public knowledge last year, many anonymous sources came out of the woodwork to lay the blame at Hunt’s door, with former staff members labeling him “an arrogant, incompetent failure.”

One senior figure told The Times at the time: “He’s running the business into the ground, and the day he resigns the staff should have a big party.

“Everyone at the business adores Jamie and they are very sad about what has happened, but morale is at rock bottom. There have been some wonderful women made redundant. I saw how Hunt eased them out.”

Another anonymous former worker added: “He always sits with his legs wide open and looks you up and down. He is testosterone central.”

The only critic to go on the record was Tara Donovan, who was the managing director of Jamie Oliver Ltd from 2005 to 2015, who pointedly told the Daily Mail she had no problems with the criticism of Hunt.

She said: “Well, I think everything was published that needed to be said.”

Jamie Oliver has always robustly defended his brother-in-law, telling the FT that it is important to hire family as you can trust them not to steal - unlike waiters, he argued, who frequently pocket bottles of wine.

He said: “Look, Paul will step down at the right time. But there are times when you need family and you need the thorough trust that family brings. In the kind of game that we’re in — whether it’s restaurants, TV, media — there is always the risk of leakage.

“When there’s dough and cash and stuff getting nicked, if it’s not customers stealing things in the toilets — and napkins — it’s staff and ingredients and bottles of wine. There’s so much leakage everywhere that it becomes normal and acceptable. When you’re genuinely trying to run some decent businesses with some good values, sometimes you’ve got to bring the family in.”

He and Hunt, who aim to make the business profitable again within four years, both blame “bad leavers” for the attacks in the press - which appear to have been mostly anonymous due to gagging orders on former staff members.

“When people get made redundant from jobs they really worked hard in, there’s a lot of stress and a lot of anger and a lot of negativity. All I can honestly say is that we’ve always paid more than the standard rate of redundancy.”

Jamie Oliver and his company declined to comment on the gagging orders or any other allegations.